For the purposes of carbohydrate analysis, it is known to label oligosaccharides and other carbohydrates with detectable labels. Radio-active labels are widely used, but many prefer to use non-radio-active materials. Various chemical labels have been proposed, e.g. providing fluorescence. Particular fluorescent labels and their use, involving analysis of labelled sugars by differential migration on electrophoresis, are described in WO-A-9428423.
Labelling is generally performed by reaction of the carbohydrate and the labelling reagent in a homogeneous solution. The resultant labelled carbohydrate is then separated.
Immobilised reaction systems are well known. For example, it has been proposed to complex labelling reagents on CELITE. Covalent carbohydrate-support conjugates are also known.